Windings and insulation for electric apparatus.



E. G. REED. wmumes AND INSULATION FOR'ELECTRIC APPARATUS.

- APPLICATION FILED JUNE 14, 1912. 1,259,444.

Patented Mar. 12, 1918.

WITNESSES: Z glN/VHTOR ATTORN EY UN ETD STATES IPATENT ()FFICE.

Er/mnsoN e. REED, or WILKINSBURG, PENNSYLVANIA, ASSIGNOR TO WESTINGHOUSE ELECTRIC AND MANUFACTURING COMPANY, A CORPORATION or PENNSYLVANIA.

WINDINGS AND INSULATION FOR ELECTRIC APPARATUS.

Specification of Letters Patent.

. Patented Mar. 12, 1918.

Application filed June 14, 1912. Serial No. 703,635.

To all whom it may concern:

Be it known that I, EMERSON G. REED, a citizen of the United States, and a resident of VVilkinsbur in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Windings and Insulations for Electric Apparatus, of which the following is a specification.

My invention relates to windings for electric apparatus and it has special reference to the winding and insulation of trans former coils.

The object of my invention i to provide a coil of the class above indicated that. shall require a relatively small quantity of insulating material and, consequently, occupy a space which is small relative to the number of turns and the current-carrying capacity of the winding.

Figure 1 of the accompanying drawings is a sectional view of a portion of a transformer coil wound and insulated in accordance with my invention. Figs. 2 and Sam respectively sectional views on the lines IIII and III-III of Fig. 1. Figs. 4. and 5 are respectively a sectional plan view and a partially sectlonal elevation of a transformer embodying my invention.

Referring to the drawings, the transformer comprises a core member 1, a secondary winding 2 and a primary winding 3, which is composed of four coil sections 1, 5, 6 and 7, a portion of a coil section being shown in detail in Figs. 1, 2 and 3.

The primary winding is subdivided into the coil sections 4, 5, 6 and 7 in order to reduce the voltage strains between layers since, by this means, it is possible to wind the 0011s of insulated wire wlthout insulation between layers except such as is provided by the insulating covering on the conductor. If the coils are rectangular in form, as shown in Fig. 4:, insulation is preferably used between layers at the corners on account of the mechanical strains to which the wire covering is subjected in winding the coils.

In addition to the space actually occupied by such insulation as had hitherto been utilized between layers, a considerable saving of space is effected by reason of the fact that the usual round wire conductors lie much closer together when strips of insulation between layers are absent, as shown in Fig. 2 of the drawings. A strip of cloth or tape is preferably used for the corner insulation and the layers are staggered to ermit a guttering action between wires of adiacent layers. I

Each section is substantially rectangular and consists of a number of layers each havmg a relatively small number of turns of cotton covered copper or other insulated conductor 8.

Insulating spacers 9 are interposed between the layers of the coil section only at its corners, as shown in Figs. 1 and 3. The spacers 9 are introduced for the purpose of protecting the relatively sharp bends in the turns of the coil at the corners, the insulation on the wire being suflicient to sustain or withstand the difference of potential existing between layers.

If the coil of Fig. 4; had been made in a double section, in accordance with prior practice, the difference of potential between layers in the coil would be at least twice as great as the difference of potential existing between layers of the coil section. Insulation of material thickness would, therefore, have to be inserted between layers and the coil would then become materially larger and less capable of radiating the heat generated in its winding.

The number of sections into which I divide the coil depends on the size and voltage of the coil and the character of the insulation with which the conductor is provided. Each section, when completed, is wrapped with a layer 11 of insulating tape, or other suitable covering.

Tubular insulating barriers 12 are interposed between the primary winding and the two portions of the secondary winding.

The sections may all be connected in series or be permanently connected in two groups of two sections.

My invention is very advantageous and extremely important in the manufacture of transformers and other similar electric apparatus on a very large scale.

I claim as my invention:

In a transformer, the combination of a. substantially rectangular coil comprising a.

plurality of sections connected in series cireuit relationship and each having layers of subscribed my name this 1st day of June, relaigvfely few conduiltor kturns that are se a 1912. rate rom one anot er y insu atin stri s at the corners only, with magnetiza le co l e EMERSON REED 5 members embracing the sides of the coils Witnesses:

intermediate the corners thereof only. W. W. KELLAMS,

In testimony whereof, I have hereunto B. B. HINES- 

